Turns out he infected it.
Posted on 02/13/2011 2:39:33 PM PST by decimon
First evidence of gene transfer from human host to bacterial pathogen offers new view of evolution, disease
CHICAGO --- If a human cell and a bacterial cell met at a speed-dating event, they would never be expected to exchange phone numbers, much less genetic material. In more scientific terms, a direct transfer of DNA has never been recorded from humans to bacteria.
Until now. Northwestern Medicine researchers have discovered the first evidence of a human DNA fragment in a bacterial genome – in this case, Neisseria gonorrhoeae, the bacterium that causes gonorrhea. Further research showed the gene transfer appears to be a recent evolutionary event.
The discovery offers insight into evolution as well as gonorrhea's nimble ability to continually adapt and survive in its human hosts. Gonorrhea, which is transmitted through sexual contact, is one of the oldest recorded diseases and one of a few exclusive to humans.
"This has evolutionary significance because it shows you can take broad evolutionary steps when you're able to acquire these pieces of DNA," said study senior author Hank Seifert, professor of microbiology and immunology at Northwestern University Feinberg School of Medicine. "The bacterium is getting a genetic sequence from the very host it's infecting. That could have far reaching implications as far as how the bacteria can adapt to the host."
It's known that gene transfer occurs between different bacteria and even between bacteria and yeast cells. "But human DNA to a bacterium is a very large jump," said lead author Mark Anderson, a postdoctoral fellow in microbiology. "This bacterium had to overcome several obstacles in order to acquire this DNA sequence."
The paper will be published Feb. 14 in the online journal mBio.
The finding suggests gonorrhea's ability to acquire DNA from its human host may enable it to develop new and different strains of itself. "But whether this particular event has provided an advantage for the gonorrhea bacterium, we don't know yet, " Seifert said.
Every year an estimated 700,000 people in the United States and 50 million worldwide acquire gonorrhea. While the disease is curable with antibiotics, only one drug is now recommended for treatment because the disease developed resistance to previously used antibiotic options over the past four decades.
Gonorrhea is a particularly serious disease for women. If left untreated, gonorrhea can lead to pelvic inflammatory disease, a painful condition that can cause sterility and ectopic pregnancy. In rare cases, men and women can develop a form of the disease that leaves the genital tract and enters the bloodstream, causing arthritis and endocarditis, an infection of the inner lining of the heart.
An ancient disease that sounds like gonorrhea is described in the Bible, noted Seifert, who has studied the disease for 28 years. Most of his research focuses on how the bacterium evades the human immune system by altering its appearance and modulating the action of white blood cells.
The gene transfer was discovered when the genomic sequences of several gonorrhea clinical isolates were determined at the Broad Institute in Cambridge, Mass. Three of the 14 isolates had a piece of DNA where the sequence of DNA bases (A's, T's, C's and G's) was identical to an L1 DNA element found in humans.
In Seifert's Feinberg lab, Anderson sequenced the fragment to reconfirm it was indeed identical to the human one. He also showed that this human sequence is present in about 11 percent of the screened gonorrhea isolates.
Anderson also screened the bacterium that causes meningitis, Neisseria meningitidis, and is very closely related to gonorrhea bacteria at the genetic level. There was no sign of the human fragment, suggesting the gene transfer is a recent evolutionary event.
"The next step is to figure out what this piece of DNA is doing," Seifert said.
###
The research was sponsored by the National Institutes of Health.
NORTHWESTERN NEWS: www.northwestern.edu/newscenter/
Later.
“An ancient disease that sounds like gonorrhea is described in the Bible, noted Seifert, who has studied the disease for 28 years.”
I guess we need dedicated people in the world like Seifert here, but, Man...what a life - studying the clap.
Clap, clap, clap,
they call him the clapper
The perfect Valentine's Day gift.
So, which came first in the evolutionary scheme?
The human or the clap virus?
Terrific! This news REALLY makes me want to get right out there and date again, LOL!
On the other hand, my documented clean bill of health will definitely be a HUGE bargaining chip when I’m ‘Husband Hunting’ again in the future.
*BIG SMILE*
Sounds like time for a major rewrite of evolutionary theory.
It is known that the human genome has integrated the entire RNA of some viruses, over the course of a vast amount of time. However, if a bacteria can get DNA from us, it could leap frog millions of years of ordinary evolution.
You mean like the way AIDs has slowed down the gay "free love" culture. Oh,wait.
It would be nice to think that people would start to wise up; but, I think they would just whine a lot and insist somebody come up with a cure.
They'll be so happy they're already getting their own internet jargon!
They don’t know, yet. Give them time to research it.
This may give medical researchers a new chance at a cure for the disease, one not involving antibiotics.
Turns out he infected it.
REAL scientists won’t go there unless they have proof. These guys do not seem like the climate prediction loonies.
“You mean like the way AIDs has slowed down the gay “free love” culture. Oh,wait.”
It did, a bit, around 1990. Then they found enough drugs to let them survive and they came back with a vengeance.
The human immune system is already pretty amazing.
Shuffling DNA around to come up with a structure that binds to just about every possible 3-D molecular shape? WOW!
Nobody supposes it alters the DNA of a bacteria; but if you have any evidence of it, I am all ears! Meanwhile there are many mechanisms bacteria have to acquire DNA for foreign sources and put them to use.
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Getting inside a cell and changing DNA is what a virus is good at. Our immune system doesn't produce viral structures.
Attaching antibodies (those 3-D shapes) to pathogens and using pyrogens and killer cells - THAT the immune system does.
Introducing DNA changes to the pathogens that prey upon you is an ineffective method, because you cannot ‘get’ them all at once, and the more detrimental the disadvantage, the more those unaffected will dominate subsequent generations.
So even if the immune system...
a) created viral like particles that could enter the bacterial cell and introduce new DNA.
b) the new DNA was to the disadvantage of the bacteria.
Then.....
c) the bacteria with the disadvantage would be out-competed by those without it.
So...at last, gonorrhea caught us!
BOLO the audience clapping gif...
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